Impact of XPM Crosstalk on SCM-Based RoF Systems

Abstract

AbstractCrosstalk effects in wavelength multiplexed subcarrier multiplexing radio-over-fiber (RoF) transmission system due to cross phase modulation (XPM) are investigated in the present paper. The crosstalk has been evaluated including the effects of dispersion along with its higher order terms (HOD) and walk-off parameter for different modulation frequencies and transmission distances. Results show that the crosstalk level can be as high as –43 dB after transmission over a 25 km of fiber with two wavelengths and 15 dBm per wavelength of transmitted power. An increment of 7 dB is observed with increase in walk-off parameter and 5 dB with increase in dispersion parameter. The crosstalk also depends upon spacing between optical wavelengths. Simulative investigation shows that increase in separation between wavelengths degrade the overall system performance, which limits the number of optical wavelengths that can be used in transmission system.